Very often we encounter PDF files that cannot be loaded or are not displayed correctly. Or they can be loaded with Adobe Reader (which is very forgiving when it comes to PDF errors) but they cannot be loaded with another tool and the customer asks 'Why?'. To debug PDF problems like these we need to dig deep in the PDF file structure.
In this article you'll find 5 applications for inspecting PDF files down to the COS object level. These tools require knowledge of PDF specification in order to understand their output. All the applications run on Windows and are GUI based.

Text extraction from PDF files is a requirement that many developers encounter in their software projects. While some people prefer to use a 3rd party library (PDFkitten for example) for this task, others want to implement it from the scratch.

First version of IFXPDFFactory for iOS is now available. It's an alpha version which means it has bugs and only the basic features are implemented but it lets you feel the API and test the concepts shown in the articles published so far.

There are 14 samples included in the samples browser application to show the features implemented so far. There is no Apple style documentation yet, but it will come.

PDF optional content (also known as PDF layers) refers to sections of content in a PDF document that can be selectively viewed, printed or hidden by document authors or consumers. This feature is now implemented in IFXPDFFactory framework.

Support for drawing images on PDF pages has been implemented. An image drawn on a PDF page is represented by the IFXPDFImage class. At this moment a PDF image can be created only from a CGImage object, later I'll add support for creating images directly from image files or memory.